Antioxidant enzyme activity, lipid peroxidation, and glycemic control among patients with type 2 diabetes mellitus in Buea Regional Hospital, Cameroon: A hospital-based case-control study

Background Oxidative stress has been suggested to play a role in the pathogenesis of type 2 diabetes mellitus (T2DM) and development of complications by altering antioxidant levels and inducing lipid peroxidation. Although diabetes mellitus patients are reported to be under oxidative stress because of prolonged exposure to hyperglycemia, the influence of glycemic control in diabetes on enhanced free-radical activity is poorly understood. This study aimed to evaluate the levels of malondialdehyde (MDA), a marker of lipid peroxidation and catalase, an antioxidant enzyme in T2DM patients with good and poor glycemic control and compare them with apparently healthy individuals. Methods A hospital-based case-control study was carried out at the Buea Regional Hospital from April to July, 2024 among patients with T2DM and age-matched healthy subjects. Sociodemographic, clinical and anthropometric data were recorded using a structured questionnaire. Levels of glucose, lipid profile, glycated hemoglobin (HbA1C), catalase and malondialdehyde (MDA) were determined by spectrophotometry. Data analyses were done using IBM SPSS version 25 for Windows. p ≤ 0.05 was considered statistically significant. Results A total of 192 participants (96 patients with T2DM and 96 healthy controls) were recruited in this study. The mean age of participants was 60.97±11.3 years with most being females (72.9%). The prevalence of lipid peroxidation was higher among patients with T2DM (71.9%) than controls (22.9%). Diet and diabetic complications were associated with lipid peroxidation (p<0.001). MDA was significantly lower in patients with good glycemic control (p <0.001). Half, 50.6% of patients with poor glycemic control had reduced catalase activity compared to only 5.3% of those with good glycemic control. There was significant strong positive correlation between HbA1c and MDA (r=0.846, p<0.001) and a significant strong negative correlation between HbA1c and catalase (r=0.846, p<0.001). Also, there was a significant negative correlation between catalase and MDA (r=-0.568, p<0.001). Conclusion Lipid peroxidation is more prevalent in T2DM patients at Buea Regional Hospital than in healthy controls and is significantly higher in patients with poor glycemic control. It is linked to diet, diabetic complications, glycemic control, and reduced catalase activity. The correlation between lipid peroxidation, antioxidant activity, and glycemic control highlights the role of oxidative stress in T2DM pathophysiology